Prostrate three times then sit on your cushion. Bring your mind to a quietstate. Start the purification with the first of the Four Opponent Powers.

1. The Power of Regret: Sincerely regret, from the depths of your heart,anything you have done to harm any living being, on this day, in this life, inall past lives. It is good to contemplate the various actions that you rememberhaving done, and then to regret all the things as well that you don't remember.The reason to regret is based on the understanding of karma: we cannot bear thethought of the future suffering that we ourselves will experience due to theharm we have done to others. We experience everything due to our past karma, ourpast actions; so having harmed others we ourselves will necessarily experiencesuffering in the future. And who wants that? We know from the present sufferingthat we do not want it, so the logic is, therefore, to clean up our act beforethe present seeds ripen as future suffering.

2. The Power of Reliance: There are two parts to this step: one, we rely uponthe doctor whose medicine we will take to purify our deluded actions, in thiscase the Buddha. It's not that we need Buddha to forgive us; rather, we relyupon him by using his methods to purify ourselves.

Two, we also rely upon others beings, the very beings we have harmed, bydeveloping compassion for them. We make the wish to purify for their sakes: allthose we have harmed in this life and in the past. Make a strong aspiration todo this practice of purification so that from now on we can only benefit others,not harm them.

Visualize Vajrasattva above the crown of your head. He is your guru manifestingin this aspect for your benefit: this is important. He is made of radiant,blissful white light. He's sitting crosslegged on a white lotus, which althoughborn out of mud is untainted by mud, just like our enlightened potential, whichis born out of our delusions but is untained by them. His face is radiant andbeautiful. His eyes are long and peaceful and full of love and compassion forus. His hair is black and held up in a top knot. His arms are crossed at hisheart, left underneath the right; the left is holding a bell, which representswisdom, the right is holding a vajra, which represents the indestructibility ofcompassion; their being crossed represents the union of these two, whichsymbolizes enlightenment itself: the development of infinite wisdom and infinitecompassion. The main thing is to really feel the presence of this enlightenedenergy above your head, and to imagine that it is a mirror image of your ownpotential.

Now, say a prayer of refuge in Guru Vajrasattva:

To the Buddha, the Dharma and the SanghaI go for refuge until I am enlightened.By this practice of meditating on Guru VajrasattvaMay I reach Buddhahood so as to benefit all sentient beings

Now visualize that light goes out of Guru Vajrasattva's heart to all the tendirections and hooks the energy of the body, speech and mind of all theenlightened beings of the universe. This light comes back and dissolves into theheart of Guru Vajrasattva, who now embodies all their energy. He is even morebrilliant and blissful than before.

3. The Power of the Antidote, which is the actual medicine, the doing of theactual practice of purification. There are three stages to the meditation, andit consists of visualization and recitation of mantra.

Purification of body: Guru Vajrasattva very compassionately sends powerful whitenectar, like coming out of a hose very forcefully, from his heart. It entersyour crown chakra and pours into your entire body, filling you completely. Itkeeps coming and it forces out all the harm you have ever done to any livingbeing with your body in the form of black inky liquid, which pours out of youand disappears into space, not one atom left. Feel completely purified. Recitethe mantra the whole time. (Until you learn it, just say it 3 times; when youknow it easily, recite at least 7)

Then feel so happy that your negativity of body is purified. Really imagine nowthat it is not possible that your body could do anything but benefit others; noway can it harm. Really want that.

Purification of speech: During the second stage of the visualization, GuruVajrasattva very happily sends powerful nectar from his heart chakra again. Itpours forcefully into your crown, filling your entire body, this time forcing upto the top of your body and to overflow all the negativity of your speech: allthe gossip and malicious speech and useless speech and lying and whatever. Allis purified by this powerful nectar, leaving your body through in the form ofinky liquid, disappearing into space, not one atom left. Recite the mantra asyou visualize this.

Again, feel so happy that your speech is now completely purified and that no waycould you do anything but say something beneficial or useful or appropriate orkind to others. Really want that.

Purification of mind: Third, Guru Vajrasattva very compassionately sends thistime light from his heart chakra. This powerful white light enters your crownchakra and fills your entire being, and just like when you turn on a light in aroom the darkness is instantly dispelled, so too, just as the light hits yourheart chakra, the darkness of the negativity of your mind, all the anger andviolence and depression and resentment and jealousy and bitterness, are allinstantly dispelled, not one atom left. Recite the mantra as you visualize this.

Again, feel happy that all your delusions, which are the cause of the harm we dowith our body and speech, are totally purified, gone, finished, and that no wayis there any space in your heart now for anything but love and kindness andforgiveness and wisdom and bliss and compassion.

Purification of even the imprints of negativity of body, speech and mind: Thistime imagine that Guru Vajrasattva sends light again and it fills you completelyand eradicates even the subtlest imprint of negative energy from your mind.Again recite the mantra.Now feel you are completely purified, and feel veryhappy. Guru Vajrasattva is happy too.

4. The Power of the Promise: The fourth step in the purification process, andsuch an important one, is the determination not to harm with our body, speechand mind again. Without this, we keep doing the same old things; determinationto not harm again is like a beacon that guides our body, speech and mind in newdirections. If you can actually vow to not do certain actions again for the restof your life, fantastic. But be realistic. If you can vow not to do them againfor a year, a month, a day, even a minute whatever is realistic. Then in generalvow to make the effort to avoid the others. This determination not to do againis what gives us the strength to turn ourselves around.

Then, very happy, Guru Vajrasattva your own guru manifesting as the BuddhaVajrasattva solely for your benefit melts into white light and absorbs into yourthrough your crown chakra. This energy of white light comes to your heart chakraand merges with your own very subtle consciousness, becoming oneness with you.Meditate on this union.

At the end of the meditation session dedicate all the merit, the positiveenergy, you have created by doing this purification to all living beings :

Through the merits of these virtuous actionsMay I quickly attain the state of a guru BuddhaAnd lead all living beings,without exception,Into that enlightened state.

May the supreme jewel bodhichittaThat has not arisen,arise and grow;And may that which has arisen not diminishBut increase more and more.

Just as the brave Manjushri and Samantabhadra,too,Realized things as they are,I,too,dedicate all these merits in the best way,That I may follow their perfect example.

I dedicate all these roots of virtueWith the dedication praised as the bestBy the victorious ones thus gone of the three times,So I might perform good works.

I dedicate whatever virtues I have ever collectedFor the benefit of the teachings and of all sentient beings,And in particular,for the essential teachingsOf venerable Losang Dragpa to shine forever.

In the land encircled by snow mountainsYou are the source of all happiness and good;All-powerful Chenrezig,Tenzin Gyatso,Please remain until samsara ends.

You are Avalokiteshvara, great treasure ofcompassion not aimed at true existence,And Manjushri, master of flawless wisdom,As well as Vajrapani, destroyer of hordes of demonswithout exception,Tsong Khapa, crown jewel of the sages of the land of snows,Losang Dragpa, at your feet I make requests.

May we not arise heresy even for a secondIn the actions of the glorious guru.May we regard whatever actions are done as pure.With this devotion may we receive the blessingsof the guru in our hearts.

In all my lives,through the victorious one,Lama Tsong Khapa,Acting in person as the Mahayana guru,May I never turn aside for even an instantFrom the excellent path praised by the victorious ones.

In whatever way you appear,glorious guru,With whatever retinue,lifespan,and pure land,Whatever noble and holy name you take,May I and others attain only these.

The four types of karmic results that the Four Opponent Powers purify:

1. The power of regret purifies the experience similar to the cause, which,let's say for killing, is to get killed, to die young or to get sick.

2. The power of reliance, Refuge and bodhicitta purify the environment result,which for killing is living in a place where the food and medicine are notconducive to good health.

3. The power of the antidote, in this case the visualization and recitation ofmantras – or whatever action one does as the actual antidote – purifies thethrowing karma that causes birth in the lower realms.

4. The power of the promise or determination not to do again purifies the actionsimilar to the cause, which in a sense is the worst result: it's the habit tokeep killing, which propels one back into the lower realms.